Determination of selenoprotein P in human plasma by solid phase extraction and inductively coupled plasma mass spectrometry

Abstract

A method based on solid phase extraction was developed for the determination of selenoprotein P as selenium in human plasma. Separation of selenoprotein P from other selenium-containing proteins was accomplished by immobilized metal-ion affinity chromatography. The selenium content was subsequently measured by inductively coupled plasma mass spectrometry (ICP-MS) monitoring the 82Se isotope. Linear response was observed in the concentration range 0.3–70.8 μg/l selenium as selenoprotein P with a correlation coefficient of 0.9994. The precision expressed as relative standard deviation was better than 2% in this range. The estimated limit of detection was 2 μg/l and the experimentally verified quantification limit was 5 μg/l, giving a relative standard deviation less than 2%.